1. Field of the Invention
The present invention has to do with sheet item, e.g. paper handling, apparatus and, more particularly, with apparatus for separating sheet items from a surface. More specifically the invention has to do with providing automatic means for separating and lifting sheet items from the printing surface of an electrophotographic drum of a copier/printer apparatus.
2. Description of the Prior Art
In printing-duplicating apparatus wherein sheet items are folded or wrapped around a cylindrical or drum-like member during printing-copying it is necessary and required that at some point in time the sheet item be passed to the next station e.g. fuser, stacker, sorter and etc. for further handling. Residual charges remaining due to the effect of the corotrons used with such apparatus produces an electrostatic attraction between the two members causing the sheet item to adhere or to stick to the other member.
Prior art solutions to this problem have included, fixed doctor blades extending across the drum or cylinder acting to peel the item away from the drum. Jets of air have been employed wherein the air blast is directed or aimed at the leading edge of the item between the item and the drum. Vacuum systems have been used to lift the sheet item from a stack and deliver them to the next station. Picker fingers have been used with the ends of the fingers extending toward the leading edge of the paper in order to lift the paper item off the drum, etc.
Rolls of adhesive strip have also been used with the adhesive surface disposed so as to contact the sheet item and then lift the item out of the way or off the drum or cylinder as the case may be. No one of these solutions has been completely effective and each has its own built in restrictions or limitations when applied to other than the specific device for which it was originally designed.